Planograph co



J. CURRY, SAFETY BRAKE FOR ELEVATORS.

APPLICATION FILED FEB. I. 1919.

. A J 7 6 J J a 4 .b 9 l I? m J J i f. L 0 5/ 1 7M 4* J 4 Z. 1 f c .H .H HHH. .w 1 1 5.21.? nn 3 E Patented July 22, 1919.

my; M

doz

l witnesses @ttozmmg THE COLUMBIA PLANOGRAPH c1. WASHINGTON. n. c.

\ rmrrnn STATES PATENT OFFICE.

JOSEPH CURRY, 0F BENTON, WASHING-TON.

SAFETY-BRAKE FOR ELEVATORS.

Application filed February 1, 1919.

To all whom it may concern:

Be it known that I, J osnrrr CURRY, a citizen of the United States, residing at Renton, in the county of King and State of Washington, have invented new and useful Improvements in Safety-Brakes for Elevators, of which the following is a specification.

This invention relates to improvementsin safety brakes for elevators and has particular application to a brake which will operate automatically upon the parting of the hoisting or lifting cable to check the downward motion of the car.

In carrying out the present invention it is my purpose to provide an automatic brake of the class described which, upon the parting of the main cable, will automatically engage the guide rails or tracks to check the downward movement of the car, and which embodies comparatively few parts and these so arranged and correlated as to reduce the possibility of derangement to a minimum.

With the above recited objects in view and others of a similar nature, the invention consists in the construction, combination and arrangement of parts set forth in and falling within the scope of the appended claims.

In the accompanying drawings Figure 1 is a fragmentary vertical sectional view through an elevator shaft with the car therein showing my invention applied.

Fig. 2 is a fragmentary horizontal sectional view through the same, part of my improved safety device being shown in section and other parts in plan.

Fig. 3 is a fragmentary perspective view of one of the operating levers.

Fig. 1 is a perspective view of one of the rail engaging members.

Referring now to the drawings in detail 1 designates an elevator shaft, while 22 indicates the vertical guide or track rails arranged within the shaft at opposite sides thereof and extending from the top to the bottom of the shaft. Within the shaft 1 is a car 3 capable of vertical movement within the shaft and secured to the opposite sides of the car 2 are guide shoes 4 designed to engage the guide rails 2 to hold the car in proper position in its upward and downward movement within the shaft.

Extending across the top of the car 3 and appropriately fast thereto are bars fia Specification of Letters Patent.

.terminate short of each other.

Patented July 22, 1919.

Serial No. 274,395.

spaced apart in parallelism and having the ends thereof projecting beyond the sides of the car or cage 3. The confronting faces of the bars 55 at the end portions thereof are preferably, although not necessarily thickened and formed with vertical grooves or channels 6 that receive the guide rail 2. Also formed in the confronting faces of the bars 55 at the end portions thereof are horizontal grooves or channels 7 that intersect the grooves 6 and open onto the end of the bar. In the present instance these grooves or channels 7 are dovetailed and slidably mounted within the respective grooves or channels 7 are clamping elements 8. In the present instance each clamping element 8 comprises a plate 9 that has its opposite side edges formed to fit into the corresponding dovetailed groove or channel 7, and a right angularly disposed jaw 10 integral with one end of the plate 9. The jaws 10 of the clamping devices at the corresponding ends of the bars 5 extend into the channels in the respective sides of the particular guide rail 2. Formed in each plate is an elongated opening 11. The openings 11 in corresponding plates 9 aline with each other and arranged within such alining openings are disks 12 that are mounted eccentrically upon a pivot bolt 13 that is mounted in grooves formed in the bars 5 as clearly shown in the drawings. Fixed upon the bolts 13 between the eccentrically mounted disks 12 are the outer ends of the levers 14c. The inner ends of these levers 14: project toward each other and Inter-connecting the inner ends of the levers 14 and pivotally connected thereto is a block 15 while encircling the block 15 is an inverted U-shaped yoke 16 that has its ends fastened to the bars 5-5or to the top of the car or "cage 3. Interposed between the upper members of the yoke 16 of the block 15 is an expansion spring 17 of suitable construction. The block 15 is connected with the hoisting cable 18 through the medium of a link 19 which, in the present case, e22- tends through an opening 20 formed in the top of the yoke 16. The outer ends of the levers 14 are formed with serrated cam heads 21" which, which under the present conditions are designed to engage the inner sides of the guide rails 2.

In practice, as longas the hoisting cable 18 is intact, the ends of the levers 14: are elevated and the cam head 21 held out of engagement with the guide rail, incident to the hoisting cable counter-actingthe spring 17. The jaws 10 of the clamping devices arealso held out of engagement with the guide rail as long as the hoisting cable is intact, owing to the fact that the disks 12 in the elongated slots 11 hold the clamping devices in inactive position.

When, however, the hoisting cable parts, the spring reacts and lowers the inner ends of the levers 1a. In the downward movement of the inner extremities of the levers 14: the cam heads 21 engage the guide rails 2. In the movement of the cam heads to engage the guide rails the pivot bolts 13 are rocked and the eccentric-ally mounted disks 12 slide the plates 9 inwardly with the effeet to engage the jaws 10 with the guide ails. Thus the jaws 10 of the clamping devices and the cam heads 21 cooperate to produce a clamping action on the guide rails so as to hold the car or cage 3 against downward movement in the shaft.

I claim 1. In a safety brake for elevators, the combination with vertical guide rails, of horizontally disposed bars secured to the top of the ear and spaced apart, the opposite ends of said bars being relatively thick and provided with intersecting vertical and horizontal grooves, a clamping element slidably mounted in the horizontal grooves at each end of the bars, a right angularly disposed jaw on each element arranged within the vertical groove and normally spaced from said guide rails, levers pivoted between the bars, a connection between the adjacent ends of said levers and the hoisting cable, whereby said levers are normally elevated, means providinga connection between the said 1evers and clamping elements, to move the latter into engagement with the guide rails when the levers are lowered, and means for lowering said levers upon the braking of the cable.

2. In a safety brake for elevators, the combination with vertical guide rails, of horizontally disposed bars secured to the top of the car and spaced apart, the opposite ends of said bars being relatively thick and provided with intersecting vertical and horizontal grooves, clamping element slidably mounted in the horizontal groove at each end of said bars, a right angularly disposed jaw on each element arranged within the vertical groove andnormally spaced fromthe guide rails, of levers pivoted between said bars, a connection between the adj acent ends of said levers and hoisting cable, whereby said levers are normally held elevated, each of said clamping elements having an elongated slot, eccentrically mounted disks carried by the opposite or outer ends of said levers and operating within the slot of said clamping element, to move the latter into engagement with the guide rails upon lowering of said levers incident to the braking of the cable, and the outer ends of said levers being provided with teeth to engage the guide rails simultaneously with said clamping element.

In testimony whereof I ttffiX my signature.

JOSEPH CURRY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. I 

